Hi Rachel,
This is all quite complicated – there were so many emails going backwards and forwards. I have tried
to summarise in the points below:
1) The answers to those specific questions are in the email below and the attached document
‘Plant Noise Statement M Local Marlborough.’
2) The ultimate answer to my second point in the email below was that they reduced the
maximum level that the equipment can work at from 50% to 44%. That came to me on a
second email much later which I will forward to you.
3) I will send you a separate email which was from Morgan Bailey from Orme Architects where
he answers my questions below about the acoustic enclosures/louvers.
4) The results of the noise survey that NSL carried out in the early hours of 23rd August are in
the attached ‘Technical Note.’ This survey was carried out when the equipment was working
at 44%.
As discussed I will speak to my manager on Monday about how best to word a condition for this case
then I will hopefully send you my final comments.
If you think there is any other information that you don’t have let me know.
Vicky
Vicky Brown
Environmental Health Officer (Environmental Control & Protection) (S&E)
Address: Wiltshire Council, Public Protection Services, Kennet House, Sergeant Rogers Way,
Hopton Park Industrial Estate, London Road, Devizes, Wiltshire. SN10 2 ET
Technical Note
Project:
M Local, Marlborough
Subject: Refrigeration plant noise readings
Date
28th August 2013
Ref:
RF84525
To:
Mike Barker, Uplands
From:
Jon Stump
Cc:
Mike,
Further to our recent site surveys to measure noise from the installed equipment, we can confirm the
following:
Measurements were taken between 05.00 and 06.00 hours on Friday 23rd August 2013. Readings were taken
with the unit on and off at 10m from the unit and at the site boundary.
Short measurements were taken so as to exclude extraneous noise sources (e.g. distant road traffic) where
possible.
Location
Plant On
Plant Off
10m from unit
30.2dB(A)
30.9dB(A)
Site boundary
34.8dB(A)
34.6dB(A)
It can be seen that, at 10m from the unit, the reading with the unit on is lower than the background reading. It
can be inferred that this is due to a variation in the background noise climate at the time and that turning the
unit on did not elevate the noise level. It can therefore be determined that the contribution from the equipment
is no louder than a level 10dB below the background reading, i.e. at 10m the plant is no louder than 20dB(A)
and is likely to be lower.
At the site boundary, the small variation in noise level with the plant on and off is, again, likely to be due to a
variation in the background noise climate. As such, the plant noise level is no louder than 25dB(A) and likely
to be lower.
Whilst compliance with the local authority criterion of 19dB(A) at the boundary cannot be conclusively
demonstrated due to the relatively high background noise climate at the time, plant noise is likely to be in
compliance.
It is noted that readings could not be taken earlier (i.e. before 05.00 hours) when background noise levels
would typically be quieter due to ongoing overnight roadworks on the High Street.
We trust the above to be of assistance at this stage. Please do not hesitate to contact us with any queries.
Kind regards,
Jon Stump